The management of groups is an essential task in collaborative learning scenarios. In a blended learning situation, in which online activities and face-to-face activities are combined, this group management becomes more complex. Different technological solutions have been proposed for supporting the group management in the CSCL field. However, these approaches fail to consider factors inherent to the blended learning scenarios. In this paper we discuss and propose a conceptualization of the main factors that condition the group management in these scenarios: the pedagogical method, the participants, the space and the history. These new conceptualization may help on incorporating more flexibility and accuracy on the whole learning design process for a wide range of learning situations.